Support only-new-issues (#19)

Fixes #16

src/run.ts

@@ -1,7 +1,9 @@
 import * as core from "@actions/core"
+import * as github from "@actions/github"
 import { exec, ExecOptions } from "child_process"
 import * as fs from "fs"
 import * as path from "path"
+import { dir } from "tmp"
 import { promisify } from "util"
 
 import { restoreCache, saveCache } from "./cache"
@@ -9,26 +11,91 @@ import { installGo, installLint } from "./install"
 import { findLintVersion } from "./version"
 
 const execShellCommand = promisify(exec)
+const writeFile = promisify(fs.writeFile)
+const createTempDir = promisify(dir)
 
 async function prepareLint(): Promise<string> {
   const versionConfig = await findLintVersion()
   return await installLint(versionConfig)
 }
 
-async function prepareEnv(): Promise<string> {
+async function fetchPatch(): Promise<string> {
+  const onlyNewIssues = core.getInput(`only-new-issues`, { required: true }).trim()
+  if (onlyNewIssues !== `false` && onlyNewIssues !== `true`) {
+    throw new Error(`invalid value of "only-new-issues": "${onlyNewIssues}", expected "true" or "false"`)
+  }
+  if (onlyNewIssues === `false`) {
+    return ``
+  }
+
+  const ctx = github.context
+  if (ctx.eventName !== `pull_request`) {
+    core.info(`Not fetching patch for showing only new issues because it's not a pull request context: event name is ${ctx.eventName}`)
+    return ``
+  }
+  const pull = ctx.payload.pull_request
+  if (!pull) {
+    core.warning(`No pull request in context`)
+    return ``
+  }
+
+  const octokit = new github.GitHub(core.getInput(`github-token`, { required: true }))
+  let patch: string
+  try {
+    const patchResp = await octokit.pulls.get({
+      owner: ctx.repo.owner,
+      repo: ctx.repo.repo,
+      [`pull_number`]: pull.number,
+      mediaType: {
+        format: `diff`,
+      },
+    })
+
+    if (patchResp.status !== 200) {
+      core.warning(`failed to fetch pull request patch: response status is ${patchResp.status}`)
+      return `` // don't fail the action, but analyze without patch
+    }
+
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    patch = patchResp.data as any
+  } catch (err) {
+    console.warn(`failed to fetch pull request patch:`, err)
+    return `` // don't fail the action, but analyze without patch
+  }
+
+  try {
+    const tempDir = await createTempDir()
+    const patchPath = path.join(tempDir, "pull.patch")
+    core.info(`Writing patch to ${patchPath}`)
+    await writeFile(patchPath, patch)
+    return patchPath
+  } catch (err) {
+    console.warn(`failed to save pull request patch:`, err)
+    return `` // don't fail the action, but analyze without patch
+  }
+}
+
+type Env = {
+  lintPath: string
+  patchPath: string
+}
+
+async function prepareEnv(): Promise<Env> {
   const startedAt = Date.now()
 
   // Prepare cache, lint and go in parallel.
   const restoreCachePromise = restoreCache()
   const prepareLintPromise = prepareLint()
   const installGoPromise = installGo()
+  const patchPromise = fetchPatch()
 
   const lintPath = await prepareLintPromise
   await installGoPromise
   await restoreCachePromise
+  const patchPath = await patchPromise
 
   core.info(`Prepared env in ${Date.now() - startedAt}ms`)
-  return lintPath
+  return { lintPath, patchPath }
 }
 
 type ExecRes = {
@@ -45,21 +112,46 @@ const printOutput = (res: ExecRes): void => {
   }
 }
 
-async function runLint(lintPath: string): Promise<void> {
+async function runLint(lintPath: string, patchPath: string): Promise<void> {
   const debug = core.getInput(`debug`)
   if (debug.split(`,`).includes(`cache`)) {
     const res = await execShellCommand(`${lintPath} cache status`)
     printOutput(res)
   }
 
-  const args = core.getInput(`args`)
-  if (args.includes(`-out-format`)) {
+  const userArgs = core.getInput(`args`)
+  const addedArgs: string[] = []
+
+  const userArgNames = new Set<string>()
+  userArgs
+    .split(/\s/)
+    .map(arg => arg.split(`=`)[0])
+    .filter(arg => arg.startsWith(`-`))
+    .forEach(arg => {
+      userArgNames.add(arg.replace(`-`, ``))
+    })
+
+  if (userArgNames.has(`out-format`)) {
     throw new Error(`please, don't change out-format for golangci-lint: it can be broken in a future`)
   }
+  addedArgs.push(`--out-format=github-actions`)
+
+  if (patchPath && (userArgNames.has(`new`) || userArgNames.has(`new-from-rev`) || userArgNames.has(`new-from-patch`))) {
+    throw new Error(`please, don't specify manually --new* args when requesting only new issues`)
+  }
+  addedArgs.push(`--new-from-patch=${patchPath}`)
+
+  // Override config values.
+  addedArgs.push(`--new=false`)
+  addedArgs.push(`--new-from-rev=`)
 
   const workingDirectory = core.getInput(`working-directory`)
   const cmdArgs: ExecOptions = {}
-  if (workingDirectory != ``) {
+  if (workingDirectory) {
+    if (patchPath) {
+      // TODO: make them compatible
+      throw new Error(`options working-directory and only-new-issues aren't compatible`)
+    }
     if (!fs.existsSync(workingDirectory) || !fs.lstatSync(workingDirectory).isDirectory()) {
       throw new Error(`working-directory (${workingDirectory}) was not a path`)
     }
@@ -67,7 +159,7 @@ async function runLint(lintPath: string): Promise<void> {
     cmdArgs.cwd = path.resolve(workingDirectory)
   }
 
-  const cmd = `${lintPath} run --out-format=github-actions ${args}`.trimRight()
+  const cmd = `${lintPath} run ${addedArgs.join(` `)} ${userArgs}`.trimRight()
   core.info(`Running [${cmd}] in [${cmdArgs.cwd}] ...`)
   const startedAt = Date.now()
   try {
@@ -91,8 +183,8 @@ async function runLint(lintPath: string): Promise<void> {
 
 export async function run(): Promise<void> {
   try {
-    const lintPath = await core.group(`prepare environment`, prepareEnv)
-    await core.group(`run golangci-lint`, () => runLint(lintPath))
+    const { lintPath, patchPath } = await core.group(`prepare environment`, prepareEnv)
+    await core.group(`run golangci-lint`, () => runLint(lintPath, patchPath))
   } catch (error) {
     core.error(`Failed to run: ${error}, ${error.stack}`)
     core.setFailed(error.message)